There is a card game called "Kasen", which is played with cards known as "Hanafuda". Only a handful of people, known as "Kaei", can call on and draw the power of the "flower". With most Kaei are men, the five students who possess the most power within the academy are referred to as the "Gokou" and are revered.

This is a story about a maiden who has dedicated herself to five male students aiming to become one of the Gokou, set in Kasen National Academy, which is a school that produces many individuals with rare talents.